Thursday, May 2, 2013

Q13/042) Solve ∣√(x−1)−2∣+∣√(x−1)−3∣=1



We know ((x1)2)-(√(x1)3) = 1
so let (
(x1)2 = t

|t | + |t -1 | = 1

t cannot be < 0 then t-1 is less than -1 and  |t | + |t -1 | > 1
t cannot be > 1 then t-1 is less than -1 and  |t | + |t -1 | > 1
so we need to check 0 < = t < = 1
if t = 1 then |t | + |t -1 | = 1
if t = 0 then |t | + |t -1 | = 1

if 0 < t < 1 then t-1 < 0 so |t | + |t -1 | = t  + 1- t = 1

so 0 < = t < = 1

or   0 <= (x1)2 <= 1
or 2 < = (x1) or <= 3

 5 < = x  <= 10

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